For many determined proponents of nuclear power, finding a solution
to the nuclear-waste
problem has become the bottom line. Even after Harrisburg, they have faith that
reactors can he made safe, if only the nuclear industry will shape up
and follow
the advice of experts. But without a solution for the waste-disposal dilemma,
legions of smoothly running reactors will only compound the problem.
Radioactive
wastes from commercial and military production are already more abundant than
all the water in the world's oceans could dilute without risking
dangerous concentrations
of radioactivity in marine organisms and sediments.

The tragic limit over which human hubris may have tripped is that nuclear waste
stays poisonous practically forever; nobody has vet invented a container for it
that won't leak, sooner or later. Environmental concern about radioactive waste
has focused on four areas: the difficulty of containment, the different kinds
of radiation, different forms of existing waste and the locations of
radioactive
waste.

For more than 35 years nuclear promoters have been saying that safely isolating
nuclear wastes would be easy. Until very recently they were saying it would be
so easy' that it wasn't necessary to bother with et. But even before the valve
failed in the Three Mile Island plants cooling system, nuclear engineers were
becoming less confident about their ability to contain ionizing radiation under
any and all conditions.

In mid-March the federal government's Interagency Review Group (IRG)
on nuclear-waste
management reported to the President that the scientific feasibility
of government's
and industry's favorite waste-disposal concept, dry storage in
geologic repositories
constructed deep in salt beds or hard nick, "remains to he
established."
This admission, though pitched in a low key, strikingly contrasts
with an earlier
draft's optimism about the feasibility of geologic storage for thousands of years. The final report, produced
by representatives of fourteen federal agencies, further advised the President,
who is expected to make the key' decision (01 geologic storage before
this article
is published, that "the preferred approach to long-term
nuclear-waste disposal
may prove difficult to implement in practice and may involve residual risks for
future generations which may be significant." The report
stressed that the
safety' of disposing of high-level wastes in mined repositories could only be
assessed by specific investigation at particular sites.

So far, only a few potential waste-repository sites have been
subjected to rigorous
geologic investigation: bedded salt deposits near Lyons. Kansas;
granite formations
in Sweden; and salt beds near Carlsbad, New Mexico (the Waste Isolation Pilot
Plant, WI PP). The Kansas salt beds were found to be riddled with
holes from con1nmercial
exploratory' operations. In February, geologists advising the Swedish Nuclear
Power Inspectorate gave a failing grade to a proposed storage site in granite.
Geologists have raised basic questions about the safety' of storing radioactive
waste in any salt formations. The WIPP site, the most thoroughly
studied by the
United States Department of Energy (DOE), is currently the focus of heavy'
criticism from environmental scientists as well as from government
nuclear scientists
outside the DOE.

How Low is Low Enough?

So far, all the design concepts for geologic repositories plan for what at best
amounts to slow' leaks and not for zero discharge of radioactive wastes. But this is not enough. A
scientific consensus
appears to be forming that any amount of radiation can cause cancer
in man.

An unverifiable amount of cell damage is caused by already existing
"background
radiation" from cosmic rays, from emanations of the natural uranium and
thorium in the earth's crust, and from residual radiation from certain natural
elements in granite and other rock. Estimates of this natural radiation range
from 100 to 250
millirem per person a year for whole-body doses Since
the average medical and dental exposure is 70 millirens annually,
human exposure
can quickly multiply above the natural background level with no increase from
nuclear power or weaponry. Even a transcontinental airplane flight acids four
millirem to the body's burden of exposure.

As more research is published on how much radiation is
"safe" for human
beings, scientists learn more about how unsafe even tiny increases
above the background
level can be. With no control possible, the damage done by the latter cannot be
measured. Even lung cancer induced by tobacco smoking may be traced
to the effect
of particles of polonium, a radioactive element collected from the
air by tobacco
leaves and deposited in the lungs of smokers.

Different kinds of ionizing radiation-labelled alpha, beta, gamma and
neutron-pose
different hazards to living cells. Alpha-emitters such as polonium and fissile
plutonium 239 can be transported in any kind of sealed container, even pockets
or briefcases, without harming anyone because alpha particles can travel only
short distances and cannot pass through the protective outer layer of
human skin.
But if an alpha particle is inhaled into the lungs, or otherwise given a chance
to reach internal organs, it adheres where it is deposited and damages cells by
accumulated radiation over the years. As little as 10-100 micrograms
of plutonium
239 in the lung is probably enough to produce a 50% chance of
inducing lung cancer.
Reactor-grade plutonium is so highly refined that one tenth as much will do the
same.

Alpha-emitting elements have very long half-lives; they include most
of the actinides:
actinium, thorium, protactinium, uranium, neptunium, plutonium,
americium, curium
and heavier elements, many isotopes of which are fissile. (Transuranic elements,
a classification often used in the media, are actinides heavier than
uranium.)

Beta particles, more than 7000 times lighter than alpha particles, can travel
farther and penetrate skin more easily. Nevertheless, like alphas,
they are most
dangerous absorbed inside the body. Most products of nuclear fission,
like those
that threatened the countryside around the Three Mile Island reactor in March,
emit beta radiation. Two that have received much attention are iodine
131, which
concentrates in the thyroid gland, and strontium 90, particularly dangerous for
infants and children because it is most readily absorbed by bone.
Another betaemitter,
tritium, is a radioactive form of hydrogen that, as a constituent
of-water, spreads
easily in the body and is therefore more easily diluted and less
toxic. Radioactive krypton, routinely released from reactors, diffuses through
the atmosphere
and adds to the average total external dose of low-level radiation received by
the public.

Most fission products also emit gamma rays. Like the neutrons
produced by nuclear
fission and fusion, gammas penetrate through skin, sinew and bone-as
well as through
heavy lead, steel and concrete shielding. X-rays are a lower-energy
form of electromagnetic
radiation, similar to gamma rays, that can penetrate the body and can
also cause
biological damage. Doctors and dentists are now encouraged to keep X-rays to a
minimum.

New information is released almost daily concerning the heightened
cancer incidence
among workers exposed to low-level radiation in uranium mining and
milling, military
reprocessing (which recovers uranium fuel used in nuclear-powered
ships and plutonium
for bomb fabrication), nuclear shipyards, soldiers involved in nuclear bomb testing
and civilians caught in its downwind fallout. Recently Ralph Nader's
Health Research
Group asked President Carter to act on a National Academy of Sciences
recommendation
that allowable occupational exposure to low-level radiation he
reduced ten fold,
from 5 rem to 0.5 rem per year, the equivalent of 20 to 50 times the level of
exposure of a chest X-ray.
The Nader group cited a British study that showed increased chromosomal damage
in workers exposed to only 2 to 3 rein a year. Dr. Alice Stewart of
the University
of Birmingham, who has been working with a study of 35,000 living Hanford workers,
says that prolonged low-dose exposure leads to proportionately more damage than
a single, larger dose. At lower doses., the body is able to repair
slightly damaged
cells well enough for them to reproduce, passing on the damage to
succeeding generations,
or to make other damaged cells that weaken the body's resistance to disease and
injury. Children born in southern Utah during the years when atomic bombs were
exploded above ground have been reported by a University of Utah medical team
to suffer 2.5 times the number of leukemia deaths as children born before and
after the testing.

For 22 years the accepted wisdom has been that annual exposure of 170 millirem
above background radiation levels was a permissible level for the
general population.
However, in 1977 the Environmental Protection Agency suggested 25 millirem as
the annual limit. The Nuclear Regulatory Commission (NRC) has adopted
that figure
as the permissible dose to the public created by the nuclear fuel cycle.

Meanwhile cancer mortality is on the rise in the United States among
all age groups.
Chemical air and water pollution, food additives and increased
ionizing radiation
from bomb-test fallout, medical procedures and nuclear reactor
operation all appear
to he culprits, each synergistically augmenting the carcinogenic effect of the
others. Given this knowledge, it seems evident that the release of carcinogens
into air, water or the food chain should he reduced rather than
permitted to escalate
over time-as ionizing radiation from increasing quantities of badly
stored wastes
is all too likely to do. (The radio
activity of commercial waste began to exceed that of military waste
last year).

Mill Tailings

The problem of containing radiation from nuclear wastes begins at the uranium
mine and at its adjacent mill, where uranium-bearing rock is crushed
and processed
and tailings are chemically separated from uranium. Currently 16 uranium mills
in the United States process 10 million to 15 million tons of ore
annually. Good
ore contains 0.2 uranium by volume. The rest is tailings; about 140
million tons
have accumulated so far in the United States, almost
uranium-free--but not radiation free.
Uranium, decaying through the ages, has produced thorium and
thorium's "daughter"
radioactive elements, including radium and radon, which are sources
of gamma radiation.

Because of thorium 230's long half-life (180,000 years), its daughter products
will remain active pollutants for hundreds of thousands of years. N
01 until fifteen
years ago, when alert public-health personnel discovered a higher incidence of
cancer in people who lived in houses
built with or on mill tailings, was their use in the construction industry and
for road building in the West curtailed. But the problem with mill
tailings persists;
tailing dumps cover many acres of ground. Wind whips the tailing dust high into
the atmosphere, where it is carried for long distances.

Covering existing tailings with asphalt or burying them and safely sequestering
new tailings is an expensive project the Department of Energy's Nuclear-Waste
Management Program is currently working on. The progress of its
efforts to protect
the atmosphere from radon, and groundwater from leached radium, will
need continued
public attention.

As part of its study of nuclear waste, the IRE; postulated several
energy futures
for the nationdifferent estimates of energy use that would result in
varying amounts
of nuclear waste. Under IRG's "Case 1" postulate of 148
gigawatts (GW)
of installed nuclear electric generating capacity in the year 2000 (the higher
Case 2 scenario projects 380 gigawatts-today the U.S. has about 50 GW
of nuclear
capacity), 1.9 billion tons of tailings will have been produced by
then. Legislation
is before Congress that would authorize EPA to issue standards and criteria for
milltailings disposal, and would establish the Nuclear Regulatory Commission's
(NBC) licensing authority over active sites and DOE's authority over inactive
sites. Assigning authority, however, cannot guarantee a solution of
the gargantuan
problem posed by the tailings.

Low-Level Wastes (LLW)

Next to mill tailings, low-level wastes, which contain small amounts
of radioactivity
and require no shielding, produce the largest physical mass of "nuclear
junk"
to be disposed of. They start accumulating at the mine shaft. Used
equipment and
such miscellaneous debris as gas filters, lab coats, paper towels and
some liquid
wastes solidified in concrete continue to accumulate through the
entire fuel cycle.
Some of it-trucks, parts of decommissioned reactors-is very bulky.

During most of the history of military and commercial use of the
atom, low-level
wastes have been buried in shallow trenches. A few years ago at the burial site
at Maxey Flats, Kentucky, plutonium was found to have migrated as far
as two miles
from the site. Of six burial sites for commercial wastes, two (West Valley, New
York, and Maxey Flats) are now closed. A third site, at Sheffield, Illinois, is
already filled to its licensed capacity. The NRC had to order the
Sheffield operator
to continue patrolling fences and maintaining trenches after the site had been,
in effect, abandoned.
Currently, commercial LLW is buried at Barnwell, South Carolina
(where the state
government limits quantities), at Beatty, Nevada, and at Hanford, Washington.
The DOE has fourteen other burial grounds. No coordinated national program for
LLW management exists yet. Niagara Mohawk Utility has applied for a permit to
build a commercial LLW incinerator at a reactor near Oswegn, New York, but the
local Sierra Club is worried that scrubbers won't keep radioactive cobalt and
cesium out of the air.

The DOE has selected a contractor to build an incinerator at the Idaho National
Engineering Laboratory. Intended for operation by late 1986, the
incinerator will
take eight years to process the existing backlog of LLW. The
rock-like radioactive
slag residue will go to ... wherever the government may decide to
build a permanent
waste repository.
Almost all low-level wastes are either solids or made solid with concrete, but
some low-level liquid wastes at a DOE facility at the test site near Mercury,
Nevada, are pumped 1000 feet do,,,,n into an underground cavity
created by a nuclear
explosion. Unknown quantities of lowlevel liquids were solidified in cement and
dumped at sea in the early days of nuclear development. It is worth
asking whether
the Nevada test-site disposal of liquid wastes could pass the
skeptical scrutiny
geologists, geochemists and hydrologists are currently giving to concepts for
using geologic formations to isolate spent fuel and high-level wastes encased
in steel and titanium.

Intermediate Waste Liquids

Intermediate-level waste liquids produced at the Oak Ridge National Laboratory
are injected into a deep underground shale bed after first being
mixed with grout.
The grout solidifies and is intended to fix the wastes in place.
Whether it does
or not, over the very long periods that some of the waste remains radioactive,
will remain in question for many thousands of years.

Transuranic (TRU) Wastes

Since both TRU waste (which contains more than ten nanocuries of
transuranic activity
per gram) and high-level waste contain long-lived actinides, they pose similar
lung-term containment problems and should be disposed of with equal care. Yet
all existing commercial TRU waste is buried, along with much larger volumes of
associated materials, in shallow trenches at commercial burial
sites (except at Barnwell, where the government of South Carolina ruled against
it). Only Hanford continues to receive commercial THU waste for burial.

The transuranic content of the DOE's THU waste is mainly plutonium.
Until recently
most of it was buried, but several years ago, at Hanford, enough plutonium was
found to have migrated from one burial trench to make a chain
reaction possible.
As a result, since 1970 DOE has stored THU waste in a retrievable
form. The major
purpose of the proposed WTPP disposal site is to store DOE THU waste produced
at Hock) Flats in the fabrication of bombs and currently stored at
the Idaho National
Engineering Laboratory. The state of Idaho has repeatedly pressured
DOE to remove
this waste.

Airborne Emissions

The fact that radioactive particles can travel through the air has been widely
known since Hiroshiosa. It became more immediately apparent at Three
Mile Island,
What is less widely known is that nuclear reactors routinely vent into the air
small amounts of gaseous radioactivity, including the nuclides
krypton-85, xenon-133, iodine-131 and carbon-14. To reduce air pollution as much as
possible, airborne
emissions from reactors, spent-fuel storage, fuel reprocessing, weapon-related
activities and waste treatment processes such as incineration and vitrification
are filtered through sand, fiberglass and other appropriate materials
that themselves
then become radioactive wastes.

A supposedly typical DOE chart of a filtration system in a spent-fuel
reprocessing
facility claims 99.97% efficiency before the gases go up a 200-foot
stack, Emissions
of radio-iodine are controlled by special absorbers. The DOE Nuclear
Waste Management
Program aims to develop "new capability in areas where more
restrictive standards
seem likely to apply in the future." It seems a virtuous intention.

High-Level Wastes (HLW)

High-level wastes are either spent-fuel assemblies or the fission products and
actinides that remain in spent fuel after plutonium and uranium have
been recovered
in reprocessing. Approximately 73 million gallons of liquid high-level wastes,
among the must toxic and hazardous substances known, are now on hand awaiting
a permanent method of disposal. They are in various forms: extremely corrosive
acid liquids; salt cakes; sludge in underground tanks; and granular, calcined
solids stored in underground bins. They consist of fission products, including
strontium 90 and cesium 137 (30-year half-lives), actinides and certain other
radioisotopes. The relatively short lifetimes of the fission products produce
rapid disintegration; most of the wastes' heat and radiation are
dissipated within
600 years of their existence. But the slower disintegrating actinides
may persist
for millions of years.

Originally, HLWs are liquids produced during the reprocessing of
defense-program
reactor fuel or the commercial reprocessing of spent fuel. Since the
United States'
only commercial reprocessing plant, owned by
Nuclear Fuel Services and located in West Valley, New York, has been
closed, high-level
wastes are new produced only at DOE military facilities in Savannah
River, South
Carolina; Richmond, Washington; and Idaho Falls, Idaho.

New double-shell steel tanks are being constructed to replace leaking tanks at
the Hanford Nuclear Reservation and to provide additional interim
storage. High-heatgenerating
cesium-137 and strontium 90 are being isolated from other wastes and
encapsulated
separately to make handling the remaining wastes easier.

Problems other than leakage have arisen with high-level waste storage. Waste at
West Valley neutralized with an alkaline solution has turned out to
be very difficult
if not impossible to remove from a carbon steel tank. After a dispute
arose between
the state of New York and the federal government over who was
financially responsible
for 600,000 gallons of waste and for the cost of dismantling the Nuclear Fuel
Services plant at West Valley, both parties arrived at a tentative
agreement that
has been rejected by environmental groups. Under the agreement, DOE
would accept
major financial responsibility for West Valley and would use its
spent-fuel pool
to store up to 1000 tons of spent fuel, and its waste-burial grounds would be
reopened. Environmental groups, including the Sierra Club's Nuclear Waste Task
Force, can he expected to mount an effective campaign against any new scheme to
encourage the accumulation of nuclear waste by storing it at West Valley while
means for its disposal remain unknown.

Since the United States has deferred indefinitely reprocessing of
commercial spent
fuel, owing to concern over keeping plutonium out of the hands of
hostile military
powers or terrorists, commercial facilities for glassifying-vitrifying-wastes
have not been developed here, as they have been at France's Cogeuma plant and
soon will he at Britain's Windscale plant. Both plants, and the
nations planning
to use their reprocessing facilities, are counting on the development
of geologic
storage for these vitrified wastes.

Reprocessing contracts such as Cogema's promise to remove all but 0.5% of the
plutonium from wastes, but experts view the promise as optimistic.
Moreover, approximately
three times as much americium is also left in the wastes; it decays
into plutonium,
so the plutonium content actually increases over the first 20,000 years. All of
the other actinides and fission products are left in the reprocessed
waste product.
If recovered plutonium is used as fuel and is again cycled through
more reprocessing,
it will he added to successive waste streams to accumulate wherever the waste
is stored, a fact generally overlooked by the proponents of
"burning tip"
the actinides.

Spent Fuel

Nuclear reactor fuel rods, each about twelve feet long, consist of a packing of
uranium-oxide fuel pellets and a zircaloy casing, called "cladding."
Approximately 40,000 of them are arranged in assemblies for encasement in the
core of a large reactor. After about three years of fission, radioactive by-products slow down the fuel pellets' ability to sustain
a nuclear reaction; the whole assembly is then considered
'spent" and removed
to a water tank for cooling and storage. Each year a 1001) MW light water reactor
discharges about 25.4 metric tons of spent fuel into storage pools adjacent to
the reactors. Only one storage pool in the United States, operated h
General Electric
at Morris, Illinois (originally intended to store spent fuel for reprocessing),
has accepted spent fuel from distant reactors, some 300 tons of it.

The storage pools at first were intended to store spent fuel rods for
five years,
but since no alternative system of storage has been devised, some
spent fuel from
our oldest commercial reactors has been cooling in them for 20 years.
The spent-fuel
rods must he carefully separated from each other to prevent the start
of a chain
reaction in the pool. The rods grow brittle with age; their cladding weakens;
their cooling water is vulnerable to cutoff; they contain higher
levels of radioactive
strontium and cesium than the reactor itself; and no one in his right
mind considers
permanent storage in a pool a good idea, whether at the generating plant or in
a very large, centralized, "away from reactor" pool.
Unfortunately no one
has yet developed and demonstrated a better plan.

Meanwhile, nuclear engineers have designed methods
for increasing the load in existing storage pools by reracking; and
some NRC spokesmen
believe that the United States could continue existing and planned
reactor operation
with no storage other than the pools until the end of the century. According to
the IEG, the U.S. has about 5000 metric tons of spent fuel now, with at least
71,000 tons anticipated by the end of the century.

From the point of view of the nuclear industry, all spent fuel is an
energy resource
that should be kept available for reprocessing into plutonium and uranium to be
refabricated into nuclear fuel. Nuclear critics worry about keeping spent fuel
cool and containing its radiation while adequate permanent isolation
technologies
are developed.

Decontamination and Decommissioning

All operating nuclear reactors and all nuclear-fuel processing
facilities, including
buildings, will sooner or later become nuclear wastes. Nuclear
reactors themselves
have an expected operating life of 30 to 35 years. The DOE has identified 560
nuclear facilities currently obsolete or expected to become obsolete in a few
years. Nobody really knows how they ill be decommissioned-if they
can be-or how
much it would cost. Estimates of decommissioning costs are not included in the
rates of utilities using nuclear power. Closing obsolete facilities
and guarding
them forever "mothballing"-has been suggested. So has encasing them
in concrete. Neither idea sounds like a winner.

Dismantling the reactors is probably the only option that will he acceptable to
environmentalists, but it does not answer the question of where and how the
chopped-up reactor will
be contained.
The NBC's Peter B. Erickson is quoted in Business Week as saying that
any mothballing
plan must take into consideration an entire range of elements,
including short-lived
isotopes such as cobalt 60, dangerously radioactive for 100 sears,
and such longlived
substances as niobium 94 and nickel 59, with halfl-ives of 20,000 and
80.000 years,
respectively, that require isolation for at least a half-million years.

Nuclear reactors looming through the mist on hillsides or the coastal horizon
look as sturdy (and as eerie) as Stonehenge; 72 commercial reactors
were operating
in the United States at the time of the Harrisburg accident, with
over 500 operating
or in the planning stages worldwide. Like the other nuclear wastes, they wont
go away by themselves.
The two plans for intermediate and permanent storage of high-level
wastes or spent
fuel have received considerable attention: the Swedish plan for
storage in granite
and the WIPP site in salt. They aim, at best, for 100 years of
absolute containment
by multiple harriers of casks, clay and rock or salt. During that
time sonic fission
products would decay to very low levels, but long-lived materials,
the heavy-metal
actinides capable of fission themselves, will probably slowly leach
through corroded
casings and dissolved glasses, through fissures in rock and
underground aquifers
into rivers and waterways. Eventually they will reach the oceans.

DOE is considering another plan to emplace nuclear wastes in clays on the sea
floor far from any continental boundary. In case of a failure of containment,
radioactive pollutants could reach the oceans even sooner.

The gamble with any plan yet proposed for storage of nuclear wastes is (1) that
none of our descendants will breach the repositories through war or
drilling for
minerals; (2) that water and heat will not concentrate fissile
materials to form
inadvertent nuclear reactors capable of producing larger quantities
of unconfined
radioactivity; (3) that ice sheets, the geologic folding of the earth, or other
unforeseen processes will not uncover the wastes; and (4) that none
of the anticipated
processes will happen faster than expected, causing the wastes to "hobble
up through the earth two decades from now because in 1979 we made a
wrong technical
decision," as Senator Glenn worried aloud at a hearing no the
IRC recommendations.
It is a most unusual gamble; no one now alive is expected to lose, if all goes
according to plan -unless a sense of guilt over endangering the future for our
present comfort and convenience is a kind of loss.

A thousand years ago, the finest architectural and engineering talents in the
western world w eye mobilized to build cathedrals. It is ironic and
disheartening
that comparable talents and even more sophisticated skills must today
he devoted
to devising foolproof garbage dumps.